5,000 marijuana plants, more than 120 pounds of dried pot, stacks of cash and handguns from seven locations in four cities, police said.

Seven men with ties to Oakland, Brentwood and Castro Valley were arrested at a converted West Berkeley warehouse at 809 Allston St. on Wednesday.

They face charges of possession of marijuana for sale, cultivation of marijuana and weapons possession violations, said Berkeley police spokesman Officer Ed Galvan.

“This is the largest marijuana bust that anyone can remember in recent history,” Galvan said Friday.

“This was just huge … and very, very professional, with state-of-the-art equipment.”

Investigators believe the growing operation had been in operation for at least two years. The investigation has been going on for five months.

Police said the growers — who were found with an estimated $500,000 worth of dried marijuana ready for street sales — had a high-end charcoal filtration system that lifted the smell of marijuana from the air.

“If you walked by the building you could not smell it because of the system,” Galvan said.

The converted warehouse at Sixth and Allston streets is not far from several restaurants, homes and businesses.

In Berkeley, police confiscated more than 2,500 marijuana plants in various stages of growth.

The space also included an extensive processing operation, where an estimated 120 pounds of harvested plants were being dried, police said.

Police also served search warrants at six locations in Brentwood, Castro Valley and Oakland.

There, they found an additional 2,500 plants in the early stages of growth at a home in Castro Valley and at two Oakland locations — on Fremont Street and on Fifth Street, Galvan said.

Bundles of cash and an assortment of weapons were found at the three locations.

Galvan said Berkeley police Detective Brian Wilson led the team of 21 Berkeley officers in the early morning bust Wednesday.

Investigators said the operation was unrelated to five raids on Thursday, led by Drug Enforcement Administration, in Oakland, Emeryville and Lafayette. In those busts, pot-laced candy and thousands of marijuana plants were seized.

“This was an all-Berkeley operation,” Galvan said. “And it went so smoothly. It was executed just perfectly.”

Police plan to release more details about the case, which remains under investigation, later.